Collaborative Research: Molecular mechanisms governing the cytoskeleton-mediated motility and distribution of peroxisomes and mitochondria in plants

合作研究：控制植物中细胞骨架介导的运动和过氧化物酶体和线粒体分布的分子机制

• 批准号: 2148207
• 负责人: Bo Liu
• 金额: $ 98.13万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-05-15 至 2026-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2148207&HistoricalAwards=false
• 关键词: Collaborative; Research; Molecular; mechanisms; governing

This research is aimed at addressing a fundamental question in cell biology that is directly associated with growth and reproduction of plants, including crops. Plant cells mobilize their highly dynamic subcellular compartments, known as organelles, to fulfill physiological functions in growth and development. This project will uncover the poorly understood mechanisms by which organelles move and distribute along molecular tracks called actin filaments within plant cells in response to internal and external signals. The focus will be on peroxisomes and mitochondria, two organelles that are physically and biochemically connected and essential for energy metabolism and survival of plants. The molecular machinery responsible for the motility and distribution of these two types of organelles will be dissected, using the small mustard plant Arabidopsis. Knowledge gained will provide fundamental insights into the principles associated with the motility of plant organelles, thereby giving perspectives on how these molecular machineries evolved. In addition, the project will train graduate and undergraduate students in modern biological skills. Hands-on research experience will be provided to first-year undergraduate students in the classroom with the goal of retaining them in science majors. Discovery-based summer trainings will be provided to undergraduates in molecular biology, genetics, cell biology, physiology and computational biology in order to prepare them for a scientific career or advanced training after graduation. Cytoskeleton-dependent active movement and distribution of organelles are fundamentally significant for cell growth, division, and signaling. However, how organelles recruit cytoskeletal motor proteins for their directional transport along the cytoskeletal tracks is complex and often under debate. This project focuses on molecular mechanisms underlying the motility and distribution of plant peroxisomes and mitochondria, multifunctional and metabolically linked organelles essential for energy metabolism and plant viability. An exploratory effort detected directional transport of peroxisomes along actin filaments and discovered candidate proteins functioning at the interface between peroxisomes/mitochondria and the cytoskeleton for organellar motility and distribution in Arabidopsis thaliana. It is hypothesized that the active long-distance movement of peroxisomes/mitochondria along actin filaments is regulated by organelle-specific receptor/adaptor proteins and GTPases, which recruit the actin-associated Myosin XI motors that energize the motility. The project includes three aims: (1) Determining the role of the actin-binding protein Peroxisomal and Mitochondrial Division 1 (PMD1) in mediating the tethering of peroxisomes/mitochondria to the actin filaments; (2) Dissecting the adaptor complex that recruits Myosin XI to the peroxisome by testing the roles of TONSOKU-associated protein 1 (TSA1), the RABE1c GTPase, and the peroxin PEX5; and (3) Dissecting the adaptor complex that recruits Myosin XI to mitochondria by testing the functions of Cardiomyopathy-Associated Protein (CMYA) and the MIRO1 GTPase. Protein immuno-affinity purification, proteomics, live-cell imaging, genetics and physiological phenotyping will be employed to untangle interactions between peroxisomes/mitochondria and the actin cytoskeleton that regulate organelle motility and advance the understanding of the impact of organelle motility on plant fitness. In addition, the project will train both graduate and undergraduate students in modern biological and computational techniques at both universities. Hands-on research experience will be provided to first-year undergraduate students in the classroom with the goal of retaining them in science majors. Discovery-based summer trainings will be provided to undergraduates in molecular biology, genetics, cell biology, physiology, and computational biology in order to prepare them for a scientific career or advanced training after graduation.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

这项研究旨在解决细胞生物学中的基本问题，该问题与包括农作物在内的植物的生长和繁殖直接相关。 植物细胞动员其高度动态的亚细胞室（称为细胞器），以实现生长和发育中的生理功能。 该项目将发现细胞器沿植物细胞内和外部信号中植物细胞中称为肌动蛋白丝的分子轨道移动和分布的机制不佳。 重点将放在过氧化物酶体和线粒体上，两个细胞器在物理和生物化学上相连，对于植物的能量代谢和生存至关重要。 将使用小型芥末植物拟南芥，将阐述负责这两种细胞器运动性和分布的分子机械。 获得的知识将为与植物细胞器的运动性相关的原理提供基本见解，从而对这些分子机器如何发展。 此外，该项目将培训现代生物学技能的毕业生和本科生。 将向课堂上的一年级本科生提供动手研究经验，目的是将其保留在科学专业的专业中。 将向基于发现的夏季培训提供分子生物学，遗传学，细胞生物学，生理学和计算生物学的大学生，以便为他们准备科学职业或毕业后的高级培训。 细胞骨架依赖性主动运动和细胞器的分布对细胞生长，分裂和信号传导至关重要。 然而，细胞器如何募集细胞骨架运动蛋白沿细胞骨架轨迹的方向转运是复杂的，并且经常在争论中进行。 该项目着重于植物过氧化物酶体和线粒体的运动性和分布的分子机制，多功能和代谢连接的细胞器对于能量代谢和植物生存能力所必需。 探索性的努力检测到过氧化物酶体沿肌动蛋白细丝的定向转运，并发现了在过氧化物酶体/线粒体之间的接口和拟南芥中分布的细胞骨架之间的界面上起作用的候选蛋白。 假设过氧化物酶体/线粒体沿肌动蛋白丝的主动长距离运动受细胞器特异性受体/适配器蛋白和GTPases的调节，构建了与肌动蛋白相关的肌球蛋白XI电机，从而募集了能量的动力。 该项目包括三个目的：（1）确定肌动蛋白结合蛋白过氧化物酶体和线粒体1（PMD1）在介导过氧化物酶体/线粒体对肌动蛋白细丝的束缚中的作用； （2）通过测试与汤孔相关蛋白1（TSA1），RABE1C GTPase和过氧蛋白PEX5的作用来剖析将肌球蛋白XI募集到过氧化物酶体中的衔接子络合物； （3）通过测试与心肌病相关蛋白（CMYA）和MIRO1 GTPase的功能来剖析将肌球蛋白XI募集到线粒体的衔接络合物。 蛋白质免疫亲和力纯化，蛋白质组学，活细胞成像，遗传学和生理表型将用于解开过氧化物酶体/线粒体和肌动蛋白细胞骨架之间的相互作用，从而调节细胞器机动性并提高对植物拟合度的影响。 此外，该项目将在两所大学的现代生物学和计算技术中培训研究生和本科生。 将向课堂上的一年级本科生提供动手研究经验，目的是将其保留在科学专业的专业中。 将向基于发现的夏季培训提供分子生物学，遗传学，细胞生物学，生理学和计算生物学的本科生，以便为他们做好毕业后的科学职业或高级培训的准备。这一奖项反映了NSF的法定任务，并认为通过基金会的知识分子优点和广泛的影响来评估NSF的法定任务。